Current work machines must have the ability to utilize various implements during operation in order to complete a multitude of work tasks. Equipment used to couple the various implements to the work machine should be easy to use so that excessive physical strain on an operator may be virtually eliminated. Furthermore, the coupling equipment must be strong and reliable in order to withstand high forces incurred during operation and designed with fewer parts for a simpler, low cost design.
A design disclosed in U.S. Pat. No. 4,747,612 issued to John B. Kuhn on May 31, 1988 utilizes a coupler or hitch assembly of the latch type. Angled jaws on the coupler act together with the ramps or angled arms on the equipment secured by the coupler to forgive vertical or horizontal misalignment during the coupling operation. The assembly has an automatically engaging latch plate which is held in a closed position by a lock pin holding mechanism with a lock pin. The lock pin holding mechanism also provides frictional restraint for holding the plate in an open position. The lock pin holding mechanism allows relatively unresisted movement of the latch plate from an open to a closed position. Movement of the latch plate is also controlled by a limit tab on the coupler to prevent the lock pin from interfering with the coupler operation. Although this system utilizes a latch type coupler, it is designed and functionable in a manner which is not conducive for typical heavy industrial quick coupling. For example, the coupler assembly requires that a pair of latch plate members with various components be spaced across the width of the work machine in order to operate in coupling an implement. Further, the latch plate members are disposed at an outer surface of a mounting bracket which makes them vulnerable to greater wear and possible damage which may reduce the functionability of the coupler assembly. Even further, there is no automatic means for forcing the latch plate members to the coupling position during decoupling.
The present invention is directed to overcoming the problems as set forth above.